1. Field of the Invention
The invention relates to an electrical connector, and more particularly to an electrical socket.
2. Related Art
At present, the most popular signal transmission specification for the computer apparatus is the universal serial bus (USB). A connector socket and a transmission cable manufactured according to this specification can be immediately used to connect a peripheral apparatus, such as a mouse, a keyboard or the like, to the computer in a plug-and-play manner.
At present, the USB specifications contain USB 2.0 and USB 3.0 specifications. Referring to FIGS. 1 to 3, a conventional USB 3.0 socket includes a plastic seat 30, a metal casing 40, one row of first terminals 10 and one row of second terminals 20.
The plastic seat 30 has one row of terminal slots 31. The front end of the plastic seat 30 is projectingly formed with a tongue 35. The tongue 35 extends horizontally.
The metal casing 40 is fixed to the plastic seat 30 and has a connection slot 41, which is disposed on the front end of the plastic seat 30 and covers the tongue 35.
The one row of first terminals 10 contain four first terminals 10, which are numbered as 1 to 4, as shown in FIG. 3. The first terminal 10 has, from front to rear, an elastic arm 11, a fixing portion 12 and a pin 13. The fixing portion 12 is positioned in the terminal slot 31 inside the plastic seat 30. The elastic arm 11 extends toward the connection slot 51 and has a projecting first connection contact 14 projecting beyond the bottom surface of the tongue 35. The pin 13 is connected to the rear end of the fixing portion 12.
The one row of second terminals 20 contain five second terminals 20, which are numbered as 5 to 9, as shown in FIG. 3. The second terminal 20 has, from front to rear, a second connection contact 21, an extension 22, a fixing portion 23 and a pin 24. The second connection contact 21 is in flat surface contact with the front section of the tongue 35 and disposed in front of the first connection contact 14. The extension 22 extends frontwards from the rear section of the tongue 35 and is connected to the second connection contact 21 and disposed between two elastic arms 11 of the first terminals 10. The fixing portion 23 is positioned in the terminal slot 31 of the plastic seat 30, and the pin 24 is connected to the rear end of the fixing portion 23.
The one row of first terminals 10 and the one row of second terminals 20 are formed by pressing the same metal sheet. After pressing, the two rows of terminals are connected to a material tape 18.
The one row of first terminals 10 do not overlap with the one row of second terminals 20 in the top viewing direction. So, when the one row of first terminals 10 are elastically moved vertically, they cannot touch the one row of second terminals 20 to cause the short-circuited condition.
However, the conventional design has the following drawbacks. Since the one row of first terminals 10 cannot overlap with the one row of second terminals 20 in the top viewing direction, the plate surface widths of the first terminal 10 and the second terminal 20 have to be reduced to avoid the overlap. Thus, the preferred widths of the first terminal 10 and the second terminal 20 cannot be freely configured to achieve the better electrical transmission requirement, and the high-speed electrical transmission requirement of the advanced electronic product cannot be satisfied.
As shown in FIG. 4 illustrating another conventional USB 3.0 socket, in order to freely configure the preferred widths of the first terminal 10 and the second terminal 20, the one row of first terminals 10 inevitably overlap with the one row of second terminals 20 in the top viewing direction. In order to prevent the one row of first terminals 10 from touching the one row of second terminals 20 to cause the short-circuited condition when they are elastically moved vertically, the vertical turning portion has to be formed between the second connection contact 21 and the extension 22 of the second terminal 20 to form a height difference. Thus, the height difference of the second terminal 20 caused by the turning portion also affects the electrical transmission, and the height difference of the turning portion also make it difficult to assemble the one row of second terminals 20 with the tongue 35 of the plastic seat, and the manufacturing method of embedded injection has to be adopted, thereby increasing the manufacturing cost.